Hot-air furnace with oil burner installation



I April 12 1949. QISCQTT r 2,466,868

HOT AIR FURNACE WITH OIL BURNER INSTALLATION 1 I Filed July 24, 1947 2 Sheets-Sheet 1 Z5 4 36 rav ia Clarke .5 07; 32, Jarnes 1777211 K3679! HOT AIR FURNACE WITH OIL BURNER INSTALLATION Filed July 24, 1947 A ril 12, 1949. D. c. SCOTT ET AL 2 Shets-Sheet 2 Patented Apr. 12, 1949 0 F F l -CE F'HOT-AI'RFURNACE WITH .OIL BURNER INSTALLATION David-.Q'Scott and James Allen'Keeley, Virginiatown, Ontario, Canada Application July 24, 1947, SerialNo. 763,314

v2 Claims. 1

' The invention appertains -;to a;standar.d;hot air furnace of the "type comprising :a combustion chamber having :a :dome atithe 'topwhi'ch is encircled by and communicates-"with a ring-shaped radiator through which products of combustion travel to thexsmoke pipe. ;In such a furnace air is heated 'by'introducing 'it into the base .of the casing through tthe'usual :coldair ducts so that it may flowxupwardly a'bout the sides of the com- 'zbustion chamber :and zazbout the .radiator ring. The heated air passes IOULtJ'Of ith'e -hot air :pipes to the rooms of the dwelling.

The object of the .present'invention .is to provide a specially :designed .oil burner-installation .for this "particular type- 0f Eliot-air furnace comprising a tubular :shell or :drumlikemember vertically arranged with its lower end seated on the floor 'of the ash-pit andiitsupp'er part extending through the regular "combustion chamber to the dome juncture 'whereit has :a sealing connection with this top portion. of the-combustion chamber -that :isolates the surrounding space from the dome. The upper end of the tubular :shell is reduced to forms. neck-which protrudes into the :dome and places it in communication with the interior of the tubular shell. Within this shell near the lower end thereof there located a pot iior the burning of .oil, which pot is perforated :about its side Wall and spaced from the wall of the shell to provide an intervening air passage.

The -portion of :the shell above the .pot constitutes a combustion chamber and the zportion below the Zpot serves to -;a.dmit air to said passage as by means of suitable openings. Oil .is fed into the put by a piping having a preheating coilrand air .is supplied .to said openings by a ,pipe forming a communication between the ash pit and the interior of the casing, which (air is preferably .forced bya fan.

Adistinctive feature is that the space surroundtheefficiency of the heatin systemis largely .en- .hanced and .a greater displacement of air is brought about. The induced flow of cold air-accelerates the circulation of hot air in the system and provides .more or less of .a closed circuit between the rooms .and thekiurnace.

The invention provides a highly "efficient oil heated furnace and one which has proved to be very satisfactory in actual operation.

Having described'the major objects and advantages of the invention subsidiary objects and advantages will appear from the ensuing detailed description and drawing:

In the drawing,

Fig. 1 is a vertical sectional view of the furnace and oil burner-installation.

Fig. 2isa front view ofthefur-nace.

Fig. 3 is a crosssection taken "on line 3-3 of 'Fig. 1.

Fig. 4 is across section taken on line 4-4 of ZF'ig. 1.

Fig. 5 is a cross section taken on line 55 of Fig.1.

Referring to the drawing by reference numerals the usual combustion chamber is denoted at 6 and the relatively smalldome thereon is indicated at l. The juncture of said dome with the constricted-part of the combustion chamber is indicated at 8. The opening "in the front of the furnace for feeding "coal is shown at"9 and this open "'ing leads to the combustion chamber and is closed "by the door 10. Belowthis doorthere is an opening H inthe front o'fthe'furnacejior'the ordinary water pan by which heated .air'is moistened. The radiator ring is denoted at l2 and this ring encircles the dome and communicates with it by means of the duct [3 whichis opposite the egress which is 'c'onn'ecteditothe smoke ,pipe Ill. The casing is represented at 1'6 and it will be understood that this provides a heating chamber ll for cold air .admitted by the return ducts It at the base so that convectivity will cause hot air to be circulated to the rooms of the building through the .delivery pipes I9 leading off the top '20 of said casing.

Having described the standard furnace with whichthe inveritionis combined the invention .it self will now'be recounted. Thisecomprises a special .oil burner installation and modification of the furnace structure to bring about an improved heating system as referred to earlier.

The oil burning unit comprises .a tubular shell \or drum-like member -21 of uniform diameter which is vertically disposed and seated on the floor of the ashpit 22.50 as to extend upwardly through the regular combustion chamber 6 and to terminate at the juncture 8 of the dome. I. Said shell 2| is of a considerably'smaller diameter than said combustion chamber and .its lower end is supplied with openings as at 23 for admittance .of .air therein supplied to the ashpit as by a return-bent pipe 24 upwardly extending from an opening cut in the door 25 thereof to the waterpan opening I l thereabove. The door 25 is sealed to make an air-tight connection and the water pan is removed to provide a passage so that air can be drawn off from the heating chamber I! in the vicinity of the combustion chamber and conducted by the external pipe 24 to the ashpit. A forced draft is produced for downward circulation of air through the pipe 24 as by an electric fan 26 located in the ashpit 22.

The upper end of the shell 2| is reduced diametrically at 21 to provide a neck 28 which projects into the dome l for a short distance. The space 29 surrounding the shell is sealed as by cement or other approved means at said juncture 8 so as to isolate it from the interior of the dome 1.

Toward the lower end of the shell 2| there is provided an internal pct 30 which is a cup-shaped member of a diameter suificiently smaller than the shell so as to provide an intervening air passage 3|. The upper end of the pot is peripherally sealed to the wall of the shell as at 32 and intermediate of the depth of the cup there is an internal bafiie plate 33 having a central opening 34. The side wall of the cup is perforated as at 35 below the bafile for ingress of air from the passage 3|.

Oil is introduced into the pot by means of a feed pipe 36 having a preheating coil 31 in close proximity to the bottom of the pot and the oil is ignited by a conventional igniter (not shown). The oil combines with air admitted by the apertures 35 to form a combustible mixture and the resultant flame ascends through the central opening in the bafiie 33 into the upper part of the shell which constitutes a combustion chamber and is supplied with a clean-out and inspection door 38.

The products of combustion pass out of the combustion chamber of the oil burner through the neck 28 into the dome 1 thence into the duct l3 and travel through the radiator ring l2 to the smoke pipe. The damper 39 of the egress M is sealed, of course, as also is the door 40 of the clean-out 4| of the radiator ring. The space 29 in the regular combustion chamber 6 of the furnace, which surrounds the shell 2|, constitutes a primary heating chamber for air which becomes highly heated therein and is delivered to the interior of the top 20 of the casing by means of a by-pass pipe 42 externally arranged and connected at its lower end to the door I 0 of the charging opening of the regular combustion chamber 6. The upper end of this pipe is connected to the casing I 6. Accordingly hot air from the primary chamber 29 is piped directly to the top of the casing for discharge through the delivery pipes Hi. If so desired any one of the several delivery pipes 9 may be connected to the by-pass pipe 42 as by a short length of fixed piping (not shown) should it be required to supply a room with additional heat. However, ordinarily the hot air piped by the by-pass augments the air heated in the hot air chamber I! which rises to the delivery pipes 9.

A humidifier 43 is shown as disposed in the upper part of the hot air chamber H, and a hot water coil 44 is depicted as disposed in the combustion chamber 45 of the oil burner for connection to a storage tank. The oil line 36 is connected to a carburetor 46 for feeding of oil to the pot 30 from a source of supply.

The invention provides a highly efficient and serviceable heating plant, and it will be understood that such changes and modifications may be resorted to in the structure as fairly come within the spirit and scope of the subjoined claims, in which the ashpit 22 is termed a lower chamber and the combustion chamber 6 is termed an upper chamber for the reason that these elements are used for a diiferent purpose in the present disclosure.

What is claimed is:

1. In combination, a hot air furnace in which there is provided a lower chamber at the bottom thereof having enclosing walls including a top wall and a floor, an upper chamber extending upwardly from said lower chamber and communicating therewith by means of an opening provided in said top wall, dome enclosing the top portion of said upper chamber, a radiator ring encircling the dome and communicating therewith and a casing providing an air heating chamber having a lower cold air inlet and an upper outlet for heated air; an oil burning unit comprising a tubular shell vertically arranged and seated on the floor of said lower chamber to extend upwardly through said upper chamber and to terminate at the juncture of said dome thereon, said shell being of a substantially less diameter than the girth of said upper chamber so as to provide an intervening space constituting a primary heating chamber for air, the upper end of said shell being reduced to provide a neck which projects into said dome, means sealing said intervening space at the top of said upper chamber to isolate it from said dome, the lower end of said shell being apertured to admit air therein, a cup-shaped oil burner pot supported in the lower part of said shell and having a spaced perforated side wall for receiving air from the apertured lower end of said shell for support of combustion, said perforated side walls of the pot being joined to said shell at a point above the perforations, means for supplying oil to said pot, a by-pass pipe communicating with said primary heating chamber and said heating chamber of the casing, and a pipe disposed externally of said casing having an upper connection therewith in the vicinity of said upper chamber and having a connection with said lower chamber.

2. In combination, a hot air furnace having a lower closed chamber provided with a top wall portion, an upper chamber extending upwardly thereover communicating therewith by means of an opening provided in said top wall portion, said upper chamber having an egress opening at its top for communicating with a radiator, and a, casing providing an air heating chamber having a cold air inlet and a hot air outlet; a fuel burning unit comprising a tubular shell vertically arranged with its lower part disposed in said lower chamber and its upper part disposed within said upper chamber, there being a space between said shell and the side wall of said upper chamber constituting a, primary heating chamber for air, said primary heating chamber communicating with said lower chamber by means of said opening which is provided in said top wall portion of said lower chamber, said upper part of said shell having a sealing junction with said top wall portion of said upper chamber to isolate said primary heating chamber, said bottom part of said shell having an opening at its end communicating with the space within said lower chamber, a cup-shaped burner pot in said lower part of said shell having a spaced perforated side wall for admitting air, said perforated side wall being joined to said shellabove the perforation, means for supplying fuel to said pot, duct a means for admitting air into said lower cham- REFERENCES CITED her, and a by-pass forming a, communication between Said primary heating chamber and the The followmg references are of record 1n the file of this patent:

UNITED STATES PATENTS upper part of said casing.

DAVID C. SCO'I'I.

Number Name Date JAMES ALLEN KEELEY 2,013,237 Funk Sept. 3, 1935 2,096,821 Noble Oct. 26, 1937 2,252,968 Frankland Aug. 19, 1941 

